Comparative study of flow condensation in conventional and small diameter tubes

Abstract

Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.

Flow boiling and flow condensation are often regarded as two opposite or symmetrical phenomena, however their description with a single correlation has yet to be suggested. In the case of flow boiling in minichannels there is mostly encountered the annular flow structure, where the bubble generation is not present. Similar picture holds for the case of inside tube condensation, where annular flow structure predominates. In such case the heat transfer coefficient is primarily dependent on the convective mechanism. In the paper a method developed earlier by D. Mikielewicz et al. [1] is applied to calculations of heat transfer coefficient for inside tube condensation. The method has been verified using experimental data from literature due to Cavallini et. al [4], Hoo-Kyu Oh et al. [5], Matkovic et. al [6], Park et al. [9] and compared to Cavallini et al. [2] and Thome et al. [11] correlations for calculations of heat transfer coefficient.